When to plant in Olney, MD
USDA Zone 7bEverything below — frost dates, hardiness zone, and what to plant when in Olney, Maryland — is derived from the closest NOAA station with complete climate normals.
In zone 7b, Olney supports a wide range of perennials year-round; the frost dates above are what set your annual vegetable timing.
Frost probability
ROCKVILLE 1 NE · 1991–2020The date the last spring and first fall frost occur, by threshold and probability. A 90% date is later in spring — and earlier in fall — than a 10% date; the 50% · 32°F row is what most gardeners plan around. These are Olney’s own odds, recorded at ROCKVILLE 1 NE.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 5 | Apr 16 | Mar 31 | Oct 12 | Oct 25 | Nov 7 |
| 32°F | Apr 15 | Apr 1 | Mar 19 | Oct 24 | Nov 6 | Nov 21 |
| 28°F | Apr 4 | Mar 22 | Mar 5 | Nov 5 | Nov 19 | Dec 6 |
Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.
What to plant now
TODAY · JULY 19Full-year planting calendar
Each bar is the exact window to take a planting action in Olney, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 18 km · complete 32°F normalsWhen stations disagree by more than a few days, that spread is real microclimate variation — elevation, water, urban heat. Judge which station best matches your own yard.
Olney planting FAQ
When is the last spring frost in Olney, MD?
Olney's average last spring frost falls near April 1 — the 50% mark at 32°F in the 1991–2020 normals. Hold tender transplants until the risk has passed, then plant out.
When is the first fall frost in Olney, MD?
The first fall frost in Olney typically arrives around November 6 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.
What hardiness zone is Olney in?
Olney is in USDA hardiness zone 7b. In zone 7b, winters are moderate — most common vegetables grow well in season.
How long is the growing season in Olney?
Olney has about 219 frost-free days — a long growing season — between the average last spring frost (April 1) and first fall frost (November 6).
When should I plant tomatoes in Olney?
For Olney, sow tomatoes indoors about February 4–February 18 and move the seedlings out around April 8, after the last spring frost.
Never miss a window in Olney
An email when it’s time to start seeds, transplant, and sow — timed to Olney’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Aspen Hill · 6 km
- Redland · 7 km
- Cloverly · 8 km
- Glenmont · 8 km
- Rockville · 10 km
- Colesville · 10 km
- Flower Hill · 10 km
- Wheaton · 11 km
Frost dates recorded at ROCKVILLE 1 NE, 8 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.
BlissGarden. "When to Plant in Olney, MD — Frost Dates & Zone 7b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00187705. Retrieved from https://blissgarden.com/maryland/olney.